The present disclosure generally relates to tear resistant solar control multilayer film. The present disclosure more particularly relates to tear resistant solar control multilayer film that includes infrared absorbing nanoparticles.
Dyed and vacuum-coated plastic films have been applied to windows to reduce heat load due to sunlight. To reduce heat load, solar transmission is blocked in either the visible or the infrared portions of the solar spectrum (i.e., at wavelengths ranging from 400 nm to 2500 nm or greater.)
Primarily through absorption, dyed films can control the transmission of visible light and consequently provides glare reduction. However, dyed films generally do not block near-infrared solar energy and consequently are not completely effective as solar control films. Dyed films also often fade with solar exposure. In addition, when films are colored with multiple dyes, the dyes often fade at different rates, causing an unwanted color changes over the life of the film.
Other known window films are fabricated using vacuum-deposited grey metals, such as stainless steel, inconel, monel, chrome, or nichrome alloys. The deposited grey metal films offer about the same degrees of transmission in the visible and infrared portions of the solar spectrum. As a result, the grey metal films are an improvement over dyed films with regard to solar control. The grey metal films are relatively stable when exposed to light, oxygen, and/or moisture, and in those cases in which the transmission of the coatings increases due to oxidation, color changes are generally not detectable. After application to clear glass, grey metals block light transmission by approximately equal amounts of solar reflection and absorption.
Vacuum-deposited layers such as silver, aluminum, and copper control solar radiation primarily by reflection and are useful only in a limited number of applications due to the high level of visible reflectance. A modest degree of selectivity (i.e., higher visible transmission than infrared transmission) is afforded by certain reflective materials, such as copper and silver. Some vacuum deposited metal films can be adversely affected by weathering, and defects in the film can form, including corrosion of the metal layers.
Solar control films having high transparency and high heat rejection contain a significant amount of silver or silver gold alloys and are very conductive. As a result, the films block RF or microwave signals from being received in certain instances such as car radio, car navigation systems and such. In many applications, solar control window films that do not block RF signals is desirable.
Solar control films are applied to a glazing structured by spraying the glazing with water, positioning the film, trimming the film (if necessary) and squeegeeing the excess water trapped between glazing (typically glass) and the film. Some amount of water is typically trapped between the glazing and film. Vacuum deposited metal layers trap water between the film and the glazing. The trapped water collects and forms discrete bubbles which may take several months to be dissipate, if at all.
Tear resistant films (also referred to herein as shatterproof films) are tough films that can be used in either free-standing configurations, such as might be used in temporary structures such as wind breaks for construction and agriculture, or may be laminated to a rigid glass or plastic substrates to provide protection from impacts, such as may occur during strong winds, vehicle accidents or criminal activity. When used in a laminated structure, tear resistant films serve to absorb and distribute impact energy, as well as providing resistance to shattered fragments being ejected from the substrate.
There is a need for improved tear resistant solar control film that has a high visible light transmission and substantially blocks infrared radiation and also has low visible light reflection and has high moisture vapor transmission rates, is stable during exposure to weathering and also does not block or hinder RF signals.